The present invention relates generally to encryption and decryption of data communications packets. More particularly, the present invention relates to pipelining such encryption and decryption to achieve faster data throughput.
Network devices operating in a wireless local-area network (WLAN) must employ the Counter Mode With Cipher-Block Chaining Message Authentication Code Protocol (CCMP) to comply with the IEEE 802.11i standard to protect the confidentiality and integrity of transmitted data from malicious attacks.
According to CCMP, the sender encrypts packets of data to be sent using a temporal key negotiated with the receiver. The receiver, upon receiving the packets, decrypts the packets using the temporal key. This scheme works well as long as the transmitted packets are separated by inter-packet gaps that are large enough to allow the receiver to complete the decryption of one packet before the next packet arrives.
However, in WLAN applications that require very high throughput, data packets are transmitted in succession with no inter-packet gaps. In addition, in IEEE 802.11n Multiple Input Multiple Output (MIMO) systems, data packets are transmitted at even higher data rates, leaving even less time for decryption.